Approximately 50% of the global population is infected with H. pylori, a bacterium in the stomach that can cause peptic ulcers and gastric cancer. hp infection is most prevalent in low-income areas of the world, and social and economic development can reduce the rate of hp infection. hp infection is often acquired at an early age, and once infected, if left untreated, the affected person will be infected with hp for life. person-to-person transmission within the family The most important route of transmission of Hp infection appears to be from mother to child and sibling to sibling, meaning that close contact is the most important cause of Hp transmission. The exact route of transmission is not well understood, but the gastro-oral, oral-oral and fecal-oral routes seem to be the most likely ones. Thus gastroenteritis may facilitate the spread of this infection. In low-income areas, the social and public environment may also play a role in the transmission of Hp. In addition, host and bacterial self factors also play a role in the acquisition and maintenance of Hp infection.